Set oven to 350 degrees.
Set oven rack to second-lowest position.
Grease a 13 x 9-inch baking pan, and line bottom of pan with parchment paper.
Combine first 5 ingredients in a bowl, mix well.
Whisk in vegetable oil and mix until dry mixture is smooth and lumps are gone.
In a medium or large bowl, with an electric mixer, cream the sugar and butter until no granules remain (about 4 minutes).
In a small bowl sift together flour, baking soda and salt.
Add to the creamed mixture along with the buttermilk; mix well until blended (about 2-3 minutes).
Add in eggs and almond extract (if using); beat very well for 5 minutes on high speed.
Transfer to a prepared cast iron pan.
Bake on second-lowest oven rack for 45-60 minutes (check for doneness after 25 minutes).